Remote-control mechanism for model airplanes



Oct. 26, 1954 OH. MARSH REMOTE-CONTROL MECHANISM FOR MODEL AIRPLANES Filed July 25, 1952 L was I mvamb CarZfLMansh ATTORNEYS Patented Oct. 26, 1954 REMdTE-CONTROL MECHANISM FOR MODEL AIRPLANES Carl H. Marsh, Ada, Okla.

Application July 25, 1952, Serial No. 300,821

This invention relates to a remote control mechanism for flying model airplanes, and more particularly, has reference to a mechanism of the character referred to whereby an operator on the ground can control the flight of a captive model airplane, such as an airplane of the type having a miniature motor powered by liquid fuel.

Most usually, mechanisms of the general type referred to above include control lines extending to the airplane, said lines being grasped by an operator on the ground, and being usually connected by a U-shaped handle. This type of control means is known as a U control, and in operation of the mechanism, the user generally grasps the handle, and by manipulation thereof, exerts pull on one or the other of the control lines extending to the model airplane, with said lines being so connected to the airplane as to cause the direction of flight to be changed responsive to the exertion of said pull. In use of a mechanism of conventional character, the operator must remain at the center of a wide circle through which the airplane travels, and must continually turn or pivot while so standmg.

The main object of the present invention is to provide a generally improved mechanism of the type stated which will be so designed as to eliminate the necessity of the operators standing in the center of the flying circle, the construction which I have devised being such as to permit one to stand at the edge of said circle.

Another important object is to provide an improved control mechanism for model airplanes which will eliminate the necessity of ones continually turning to keep the airplane in sight and to prevent fouling of the control lines, my construction being adapted to permit one to even remain seated if he so desires, while still being able to keep the airplane in sight at all times.

Still another object is to provide a remote control mechanism for model airplanes which will eliminate a deficiency which I have noted in connection with mechanisms now in use, namely, the tendency of the airplane to be lost or to crash into a group of bystanders when the control handle accidentally slips from the users hands.

Still another object is to provide a mechanism as stated which will be particularly designed to facilitate instruction of beginners in methods of using the conventional U controls.

Other objects will appear from the following description, the claims appended thereto, and from the annexed drawing, in which like reference characters designate like parts throughout the several views, and wherein:

Figure 1 is a side elevational view of a remote control mechanism for model airplanes formed in accordance with the present invention;

Figure 2 is an elevational view of the upper portion of said mechanism, taken from the right of Figure 1; l Figure 3 is an elevational view of the upper por- 3 Claims. (01. 272-41) tion of the standard incorporated in the device; and

Figure 4 is an enlarged, fragmentary view partly in elevation and partly in longitudinal section, showing the center portion of the standard and the rotatable block carried thereby.

Referring to the drawings in detail, the reference numeral II) has been applied to a fiat, horizontal base plate which in the present instance, but not necessarily, is of rectangular outer configuration. Secured to the underside at the base plate It], and spaced about the periphery thereof, are depending feet 12 whereby the base plate can be supported in a slightly elevated position above a supporting surface, not shown.

Fixedly secured to the center portion of the base plate l0, and upstanding from the base plate, is a flat, relatively elongated support plate it, and screwed or otherwise fixedly attached to the upper portion of said support plate is a mounting plate [6. A tubular standard 18 extends vertically from the support plate, and is attached to the support plate by means of the mount'mg plate It, said mounting plate being welded or otherwise fixedly connected to the lower end portion of the standard.

A lower collar 20 is circumposed about the lower end portion of the standard 18, and is fixedly secured to the standard in a selected position of adjustment longitudinally of the standard, by means of a set screw or the like. An upper collar 22 is similarly attached to the standard, at the upper end thereof.

The parts so far described form a base designated generally by the reference numeral 23, all parts of said base being stationary during use of the device constituting the present invention.

Rotatably mounted upon the standard it are lower and upper sleeves '24, 26 respectively. A washer 28 is interposed between the lower sleeve 24 and the lower collar 20, to assure freedom of rotation of the lower sleeve. The lower collar 20, as will be appreciated, supports the sleeve 24 for rotatable movement upon the standard is, at a selected location taken longitudinally of the standard.

A washer 30 is interposed between the sleeve 26 and collar 22, and assures freedom of rotation of the sleeve 26 while at the same time preventing movement of said sleeve 26 in a direction away from the sleeve 24.

Carried by the sleeves 24, 26 is a c-shaped frame designated generally by the reference numeral 32, said frame being formed from a single length of fiat bar material bent to shape, and including a bight 34 extending in parallelism with the standard I8. Legs 36 are horizontally disposed, said legs being integral at one end with the respective ends of the bight 34, and being welded or otherwise fixedly connected at their other ends to the sleeves 24, 26 respectively.

From the construction so far described, it is apparent that the frame 32 will rotate about the axis of the stationary standard ill, with the a 3 sleeves 26, 25, the bight 34 being moved bodily through a circular path having said axis as its center.

A control rod 38 is carried by the base, said rod being of elongated formation, and extending longitudinally of and within the tubular standard I8. The rod 38 is mounted in the standard for reciprocating motion in the direction of its own length, and has its lower end projecting below the lower end of the standard. Pivotally connected to the lower end of the rod 38 is the center leg of a double bell crank All, said bell crank being pivotally mounted at 42 upon the lower end portion of the support plate id, for movement about a horizontal axis.

Connected to the outer ends of the other legs of the bell crank it are flexible main control elements id, said elements 4 being of any desired length, and being joined at their outer ends by a U-shaped handle MS of the type gen erally embodied in the conventional U controls used for model airplanes.

It will thus be apparent that if pull is exerted upon the upper main control element M in a direction from the support plate M, the bell crank all will be swung counter-clockwise, and will impart movement in an upper direction to the main control rod 38. Conversely, pull exerted upon the lower main control element M will impart clockwise movement to the bell crank rid, which clockwise movement will be effective to cause downward movement of the control rod 38.

Referring now to Figure 4, I make rigid with the upper end of the main control rod 33 spaced pairs of lug 48, the lugs of each pair extending radially and outwardly from the control rod in opposite directions, and said pairs being spaced longitudinally of the control rod. En-

gaged between the pairs of lugs 33 is a rotary block at, said block being mounted for rotation upon the intermediate portion of the standard, substantially midway between the rotatable sleeves 2d, 26. The lugs d8 overlie the opposite ends of the block 50, and accordingly, reciprocating motion of the control rod 38 is effective to cause reciprocating motion of the block 56, longitudinally of the standard it, conjointly with the main control rod.

It may be noted that in some commercial embodirnents of the invention, the pairs of lugs d8 might, instead of being permanently and fixedly secured to the main control rod 33, be loose upon the main control rod, and when this construction is used, set collars 52 can be secured to the main control rod 38, above and below the respective pairs of lugs =38, to hold the lugs in proper position relative to the control rod. In any event, even where the lugs 88 are permanently and fixedly attached to the rod 33, the collars 52 are utilized as shown in Figure 4, to guide the rod 33 during its straight line move ment in opposite directions within the standard it.

Formed in the intermediate portion of the standard It are diametrically opposite, aligned, longitudinal slots 54, the lugs til projecting through the respective slots to hold the rod 38 against rotation during its reciprocating motion, and also to project laterally and outwardly from the standard over the end surfaces of the block 553.

It will thus be seen that the block 56 will move upwardly and downwardly upon the standard l8, responsive to pull exerted upon one or 4 the other of the main control elements 44. In any position to which the block 59 is moved, it is free to rotate upon the standard.

Welded or otherwise fixedly secured to the side wall of the rotary block 50, and projecting outwardly from said rotary block, is an L-shaped bracket 56, a link 58 being pivotally connected at its lower end to said bracket and extending in parallelism with the standard l8. At its upper end, the link 58 is pivotally connected to the outer end of the center leg of a double bell crank .80 pivoted at 62 upon the upper horizontal leg 36 of frame 32.

Flexible secondary control elements 64 are respectively connected to the other legs of the bell crank 60, and extend through a single eye 66 mounted upon the outer end of a bracket member 68 of inverted L-shape bolted or otherwise fixedly connected to the upper end portion of the bight 34, and projecting outwardly from said bight. The secondary control elements 84, after being extended through the eye 66, are connected to the controls of the model airplane A.

Also made rigid with the block 5b is a radial arm 10, having an aperture at its outer end, receiving an elongated rod member 12. The rod member 72 is interposed between the standard l8 and the bight 34 of the frame 32, and is disposed in parallelism with the standard and bight. At its opposite ends, the rod member 52 is extended through registering openings formed. in the horizontal legs 36 of the frame, the ends of the rod member being threaded to receive nuts is whereby the rod member is held in place upon the frame 32.

A spring it is interposed between the arm iii and a cross pin 78 carried by the rod member, the spring 16 being circumposed about the rod member. The purpose of the spring it is to compensate for the weight of the rotary block 50. Additionally, the spring serves the purpose of maintaining the several parts of the device in a normal, neutral position such as that illustrated in Figure l.

The functional characteristics of the invention may now be readily noted. Obviously, the main control elements :14 can be of substantial length, thus to permit the operator to stand. or be seated at the edge of a flying circle traveled by the airplane A about the base 23. The secondary control elements 54, of course, can also be of any desired length; In use, the operator exerts pull upon one or the other of the main control elements M. This pull is translated into swinging movement of the bell crank it and this, in turn, causes up or down movement of the controlrod 38. The up or down movement of the control rod transmits similar movement to the rotary block 50, and through the medium of the link 53, swinging movement is imparted to the bell crank 60. Swinging of the bell crank Bil exerts pull upon one or the other of the secondary control elements 64, thus controlling the flight of the airplane A.

During the flight of the airplane, it will travel in a circle about the base 23, and will lead the frame 32 during such travel. As a result, the frame 32 rotates freely about the standard it, with the sleeves 24, 2G and the rotary block 5Q.

It is considered to be an important characteristic of the invention that the airplane travels freely within a circle, carrying the frame 32 about the standard 3. Despite the fact that the-frame 32 is mounted onthe standard for free rotation,

with its associated rotary block 5!), the block 59 is still moved downwardly upon the standard as desired, during the controlling of the flight of the airplane. The controlling of the flight of the airplane does not in any Way affect adversely the circling of the base by said airplane.

It is also considered to be an important characteristic of the invention that these results are achieved without necessity of the user standing and turning about at the center of the flying circle. The user can remain any desired distance from the center of the fiying circle, thus to be comfortably disposed while still keepin the airplane in sight and fully controlling the flight of the airplane. The device thus has particular adaptability for use by handicapped persons who heretofore have not been able to operate a model airplane of this type, except perhaps with considerable difficulty. Still further, the device lends itself to the giving of group instruction, since one demonstrating the use of U controls can conveniently position himself to permit his every movement to be observed by those receiving the instruction and need not continually turn away from said group in following the flight of the airplane.

It is believed apparent that the invention is not necessarily confined to the specific use or uses thereof described above, since it may be utilized for any purpose to which it may be suited. Nor is the invention to be necessarily limited to the specific construction illustrated and described, since such construction is only intended to be illustrative of the principles of operation and the means presently devised to carry out said principles, it being considered that the invention comprehends any minor change in construction that may be permitted within the scope of the appended claims.

What is claimed is:

1. A remote control mechanism for model airplanes comprising: a stationary base; a double bell crank pivotally connected medially between its ends to the base to rock thereon; a pair of main control elements connected at one end to and terminating at the end legs of the double bell crank, said elements having handle means at their other ends to be grasped by a user for converging pull on a selected element into rocking of the bell crank in a selected direction; a control rod reciprocating on said base and connected at one end to the middle leg of said bell crank so as to be reciprocated responsive to rocking of the bell crank; a second double bell crank having a medially disposed fulcrum point and mounted to rotate bodily about said rod; a linkage connected between the middle leg of the second bell crank and the rod and arranged to rock the second bell crank in duplication of the rocking movement of the first bell crank, responsive to reciprocation of the rod; spring means connected to said linkage for normally maintaining both bell cranks and the rod in a neutral position; and secondary control elements terminating at one end at and extending from the end legs of the second bell crank for controlling the flight of a model airplane.

2. A remote control mechanism for model airplanes comprising: a stationary base; a double bell crank fulcrumed medially between its ends on the base to rock in opposite directions thereon; a pair of main control elements connected at one end to and terminating at the end legs of the double bell crank, said elements having handle means at their other ends to be grasped by a user for converting pull on a selected element into rocking of the bell crank in a selected direction; a control rod reciprocating on said base and connected at one end to the middle leg of hell crank so as to be reciprocated responsive to rocking of the bell crank; a second double bell crank having a medially disposed fulcrum point and mounted to rotate bodily about said rod, said second bell crank being of the same size as the first bell crank; a linkage connected between the middle leg of the second bell crank and the rod and arranged to rock the second bell crank to an extent duplicating the rocking movement of the first bell crank responsive to reciprocation of the rod; spring means connected to said linkage for normally maintaining both cell cranks and the rod in a neutral position; and secondary control elements terminating at one end at and extending from the end legs of the second bell crank, rocking of the second bell crank in a selected direction being eifective to exert pull on a selected secondary control element to an extent duplicating the pull of the corresponding main control element, for controlling the flight of a model airplane.

3. A remote control mechanism for model airplanes comprising: a stationary base; a tubular standard carried by the base and having at least one longitudinal slot; a double bell crank fulcrumeol medially between its ends on the base to rock in opposite directions thereon; a pair of main control elements connected at one end to and terminating at the end legs of the double bell crank, said elements having handle means at their other ends to be grasped by a user for converting pull on a selected element into rocking of the bell crank in a selected direction; a control rod reciprocating in said standard and connected at one end to the middle leg of said bell crank so as to be reciprocated responsive to rocking of the bell crank; a frame mounted on said standard to rotate thereabout; a second double bell crank fulcrumed medially between its ends on the frame so as to be rotated bodily therewith about the standard, said second bell crank being of the same size as the first bell crank; lug means projecting laterally from the rod through said slot; a sleeve rotating on the standard and supported on said lug means for reciprocation with the rod; a link connected between the middle leg of the second bell crank and the sleeve to rock the second bell crank to an extent duplicating the rocking movement of the first bell crank, responsive to reciprocation of the rod; spring means mounted on said frame compensating for the weight of said sleeve and normally maintaining said sleeve, both bell cranks and the rod in a neutral position; and secondary control elements terminating at one end at and extending from the end legs of the second bell crank, rocking of the second bell crank in a selected direction being efiective to exert pull on a selected secondary control element to an extent duplicating the pull on the corresponding main control element, thereby to control the flight of a model airplane.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,390,307 Kelecius Dec. 4, 1945 2,404,922 Padgett July 30, 1946 2,603,910 Jones July 22, 1953 

